diff --git a/cli/internal/acp/server.go b/cli/internal/acp/server.go
index dc944586..6e6f64ce 100644
--- a/cli/internal/acp/server.go
+++ b/cli/internal/acp/server.go
@@ -19,7 +19,7 @@ import (
 )
 
 type Backend interface {
-	Models(context.Context, string) (app.ACPModels, error)
+	Models(context.Context) (app.ACPModels, error)
 	CurrentModel(context.Context, string) (string, error)
 	SetModel(context.Context, string, string) (app.ACPModels, error)
 	List(context.Context, *string, *string) (protocol.SessionPage, error)
@@ -237,7 +237,7 @@ func (a *adapter) setup(message request) {
 		return
 	}
 	// Provider discovery can be slow; do it before acquiring or pausing a lease.
-	models, err := a.backend.Models(a.ctx, params.SessionID)
+	models, err := a.backend.Models(a.ctx)
 	if err != nil {
 		a.respond(message.ID, nil, err)
 		return
@@ -259,7 +259,7 @@ func (a *adapter) setup(message request) {
 		a.respond(message.ID, nil, err)
 		return
 	}
-	models.Current, err = a.backend.CurrentModel(a.ctx, attachment.SessionID)
+	currentModel, err := a.backend.CurrentModel(a.ctx, attachment.SessionID)
 	if err != nil {
 		if prior != nil {
 			prior.resumeObservation()
@@ -271,9 +271,7 @@ func (a *adapter) setup(message request) {
 		a.respond(message.ID, nil, err)
 		return
 	}
-	if !slices.Contains(models.Available, models.Current) {
-		models.Available = append(models.Available, models.Current)
-	}
+	models = models.WithCurrent(currentModel)
 	a.stopPrior(attachment.SessionID)
 	a.mu.Lock()
 	current := newSession(a, attachment)
diff --git a/cli/internal/acp/setup_test.go b/cli/internal/acp/setup_test.go
index 60a381f8..c76c4fbc 100644
--- a/cli/internal/acp/setup_test.go
+++ b/cli/internal/acp/setup_test.go
@@ -24,7 +24,7 @@ type setupBackend struct {
 	calls   chan string
 }
 
-func (b *setupBackend) Models(context.Context, string) (app.ACPModels, error) {
+func (b *setupBackend) Models(context.Context) (app.ACPModels, error) {
 	return app.ACPModels{Current: "fixture/model", Available: []string{"fixture/model"}}, nil
 }
 
@@ -154,7 +154,7 @@ type refusedResumeBackend struct {
 	prior *session
 }
 
-func (b refusedResumeBackend) Models(context.Context, string) (app.ACPModels, error) {
+func (b refusedResumeBackend) Models(context.Context) (app.ACPModels, error) {
 	return app.ACPModels{}, nil
 }
 
diff --git a/cli/internal/app/acp.go b/cli/internal/app/acp.go
index a5ff2497..c3368f42 100644
--- a/cli/internal/app/acp.go
+++ b/cli/internal/app/acp.go
@@ -19,31 +19,28 @@ type ACPModels struct {
 	Available []string
 }
 
-func (a *ACPConnection) Models(ctx context.Context, id string) (ACPModels, error) {
+func (a *ACPConnection) Models(ctx context.Context) (ACPModels, error) {
 	profiles, err := daemon.ProviderProfiles(ctx, a.connection)
 	if err != nil {
 		return ACPModels{}, err
 	}
-	provider := profiles.Active
-	model := profiles.Providers[provider].Model
-	models := ACPModels{Current: provider + "/" + model}
-	if id != "" {
-		models.Current, err = a.CurrentModel(ctx, id)
-		if err != nil {
-			return ACPModels{}, err
-		}
-	}
+	models := ACPModels{}
 	for _, catalog := range configuredModels(ctx, a.connection, profiles) {
 		for _, model := range catalog.models {
 			models.Available = append(models.Available, catalog.provider+"/"+model)
 		}
 	}
-	if !slices.Contains(models.Available, models.Current) {
-		models.Available = append(models.Available, models.Current)
-	}
 	return models, nil
 }
 
+func (models ACPModels) WithCurrent(current string) ACPModels {
+	models.Current = current
+	if !slices.Contains(models.Available, current) {
+		models.Available = append(models.Available, current)
+	}
+	return models
+}
+
 func (a *ACPConnection) CurrentModel(ctx context.Context, id string) (string, error) {
 	session, err := daemon.GetSession(ctx, a.connection, id)
 	return session.Provider + "/" + session.Model, err
@@ -61,14 +58,15 @@ func (a *ACPConnection) SetModel(ctx context.Context, id, value string) (ACPMode
 	if provider+"/"+model != value {
 		return ACPModels{}, &daemon.APIError{StatusCode: 400, Code: "model_unavailable", Message: "The selected provider is no longer configured; resume to refresh models"}
 	}
-	configuration, err := daemon.GetSessionConfiguration(ctx, a.connection, id)
-	if err != nil {
+	if err := switchModel(ctx, a.connection, id, modelChoice{provider, model}, a.token); err != nil {
 		return ACPModels{}, err
 	}
-	if err := daemon.SelectACPModel(ctx, a.connection, id, a.token, daemon.ModelSelectionRequest{Provider: provider, Model: model, ETag: configuration.ETag}); err != nil {
+	models, err := a.Models(ctx)
+	if err != nil {
 		return ACPModels{}, err
 	}
-	return a.Models(ctx, id)
+	current, err := a.CurrentModel(ctx, id)
+	return models.WithCurrent(current), err
 }
 
 func (s *Service) ConnectACP(ctx context.Context, token string) (*ACPConnection, error) {
diff --git a/cli/internal/app/model_select.go b/cli/internal/app/model_select.go
index 36798dc8..d7d80af3 100644
--- a/cli/internal/app/model_select.go
+++ b/cli/internal/app/model_select.go
@@ -77,12 +77,12 @@ func chooseModel(listed []providerModels, active, requested string) (modelChoice
 
 // switchModel moves an idle session to the chosen model without making it the
 // default for new sessions.
-func switchModel(ctx context.Context, conn *daemon.Connection, sessionID string, choice modelChoice) error {
+func switchModel(ctx context.Context, conn *daemon.Connection, sessionID string, choice modelChoice, attachmentToken string) error {
 	configuration, err := daemon.GetSessionConfiguration(ctx, conn, sessionID)
 	if err != nil {
 		return err
 	}
-	_, err = daemon.SelectModel(ctx, conn, sessionID, daemon.ModelSelectionRequest{Model: choice.model, Provider: choice.provider, ETag: configuration.ETag})
+	_, err = daemon.SelectModel(ctx, conn, sessionID, daemon.ModelSelectionRequest{Model: choice.model, Provider: choice.provider, ETag: configuration.ETag, AttachmentToken: attachmentToken})
 	return err
 }
 
diff --git a/cli/internal/app/prompt.go b/cli/internal/app/prompt.go
index 8a103e9a..f7ffbdc3 100644
--- a/cli/internal/app/prompt.go
+++ b/cli/internal/app/prompt.go
@@ -56,7 +56,7 @@ func (s *Service) RunPrompt(ctx context.Context, options PromptOptions) (PromptR
 		sessionID = session.ID
 	} else {
 		if model != "" {
-			if switchErr := switchModel(ctx, conn, sessionID, choice); switchErr != nil {
+			if switchErr := switchModel(ctx, conn, sessionID, choice, ""); switchErr != nil {
 				return PromptResult{}, switchErr
 			}
 		}
diff --git a/cli/internal/daemon/acp.go b/cli/internal/daemon/acp.go
index ed534201..ef92848e 100644
--- a/cli/internal/daemon/acp.go
+++ b/cli/internal/daemon/acp.go
@@ -69,15 +69,6 @@ func ReleaseACP(ctx context.Context, conn *Connection, id, token string) error {
 	}}, []int{204}, func(_ []byte, _ int) error { return nil })
 }
 
-func SelectACPModel(ctx context.Context, conn *Connection, id, token string, selection ModelSelectionRequest) error {
-	headers, err := observedHeaders(selection.ETag)
-	if err != nil {
-		return err
-	}
-	headers.Set("Albedo-Attachment-Token", token)
-	_, err = patchSessionWithHeaders(ctx, conn, id, headers, map[string]any{"model": selection.Model, "provider_profile": selection.Provider})
-	return err
-}
 func (c *ChatClient) SeedCursor(cursor protocol.Cursor) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
diff --git a/cli/internal/daemon/models.go b/cli/internal/daemon/models.go
index 4c2546ec..494c1125 100644
--- a/cli/internal/daemon/models.go
+++ b/cli/internal/daemon/models.go
@@ -30,7 +30,7 @@ type CompactAtResult struct {
 	Message, ETag string
 }
 type ModelSelection struct{ Provider, Model, Protocol, Effort, ETag, DefaultETag string }
-type ModelSelectionRequest struct{ Model, Provider, Effort, ETag string }
+type ModelSelectionRequest struct{ Model, Provider, Effort, ETag, AttachmentToken string }
 type ModelChangeRequest struct {
 	Model, Provider, Effort, ETag, DefaultETag string
 	MakeDefault                                bool
@@ -102,7 +102,14 @@ func SelectModel(ctx context.Context, conn *Connection, id string, request Model
 	if request.Effort != "" {
 		body["effort"] = request.Effort
 	}
-	session, err := patchSession(ctx, conn, id, request.ETag, body)
+	headers, err := observedHeaders(request.ETag)
+	if err != nil {
+		return ModelSelection{}, err
+	}
+	if request.AttachmentToken != "" {
+		headers.Set("Albedo-Attachment-Token", request.AttachmentToken)
+	}
+	session, err := patchSessionWithHeaders(ctx, conn, id, headers, body)
 	return ModelSelection{Provider: session.Provider, Model: session.Model, Protocol: session.Protocol, Effort: session.Effort, ETag: session.ETag}, err
 }
 func ChangeModel(ctx context.Context, conn *Connection, id string, request ModelChangeRequest) (ModelSelection, error) {